Question

Which among the following is the most probable reason for preference of cisatracurium over atracurium?

• A. Decreased histamine release
• B. Increased histamine release
• C. Due to elimination by Hofmann elimination
• D. Increased CNS toxicity

Hint:

Both share Hofmann elimination; the real edge is no histamine release.

Answer 1

The Correct Option is A

Step 1: Frame the comparison as "what makes cisatracurium safer." Identify the trait that is uniquely better, not one shared by both agents.
Step 2: Hofmann elimination is common to the whole atracurium family, so option c is a shared property and cannot explain a preference.
Step 3: Atracurium liberates histamine, causing rash, hypotension and bronchoconstriction. Cisatracurium is essentially free of this effect, giving a calmer hemodynamic course with no change in heart rate or blood pressure.
Step 4: Cisatracurium also generates less laudanosine, so CNS excitation and seizure risk fall rather than rise, ruling out option d. The decisive edge is the absence of histamine release.
\[\boxed{\text{Decreased histamine release}}\]